Research On Z Source Integrated On Board Chargerapplied On Electric Vehicle

Currently, the ac charging form is used in electric vehicles,which contain on-boardcharger and have normal charging power,long charging time. It can be considered toshare a set of system because the body of the car charger is similar to the electric carmotor drive system.This article study a electric vehicle integration charger based on the Z sourceinverter. The charger makes full use of the original Z source inverter and motor, controlcircuit of electric vehicle, needing little switches and realizing charging function.themethod can save a set of charging equipment.compared with greater power charger, itcan decrease the cost of electric vehicles, make charge convenient and satisfy the need offast charging.Firstly, attention is focused on the mathematical modeling of Z source rectifier,establishing its small signal model, and obtaining the transfer function of the circuit.simulation display that the inductor current and the capacitor voltage is presentoscillation.On this basis, according to a unipolar PWM modulation mode, the article putsforward a new modeling method of the rectifier that Coupling relationship of modulationfactor and shoot–through duty is considered.Finally,the relevant transfer function hasbeen simulated by MATLAB, simulation verifies the new modeling method.At the same time, the control system is the core of the charger part and the basis ofthis research work. This article set the Z source rectifier control system model inMATLAB, the simulation implements the power factor correction and output voltageadjustment. Current harmonic and its influencing factors are analyzed in theory. Thispaper developed a prototype of Z source rectifier. Hardware consists of the multiplexedoutput power supply, drive circuit, signal modulation circuit and interface circuit.Software part is divided into current loop and voltage loop, zero passage detection andsine computing program.In the integrated charger, motor windings can be used as the AC side filter inductor,but make sure that motor rotor is static when charging. This paper presents two motorwindings program, analyzes the effect of the rotor position on the equivalent inductance,explore rotor motion when motor wind is accessed. Then,simulation verify aboveanalysis.